Research

Nitrogen biogeochemistry in terrestrial ecosystems - Nitrogen cycling is the mostly studied biogeochemical process in ecology and temperate forest is one of the most familiar ecosystems to general public and to professional ecologists, yet we still lack many mechanistic understandings in this fundamental process in temperate forests and such lack of understandings limits our abilities to interpret natural patterns of N cycling, to predict N cycling in human modified and managed systems, and to prevent a series of environmental consequences related to N alterations.

Urban ecology and the alterations of ecosystem processes - Urbanization is the most dramatic changes human beings have ever brought to the earth, fundamentally alters ecosystem structures, functions, species compositions and interactions. Urbanization is the necessity of civilization, understand ecological changes accompanying urbanization is thus essential. I have been involved in studying both "ecology in the city" (study individual patches in a city) and "ecology of the city" (treat the whole city as an ecosystem). Study ecosystem processes in urban remnant "natural" patches and human created patches allows us to understand the human impacts of urbanization, and ecosystem alleviation of human pollutions. Study city "as a whole" allows us to understand the constraints on urban development and the effect of urbanization to neighboring ecosystems from a landscape perspective.

Landscape configuration and Watershed sciences - One of the current directions of my lab is to understand nutrient cycling in a watershed with mixed land use, and to address non-point source pollution associated with various human activities. Many factors, including sizes of different land use patches, their relative positions, and different biogeochemical processes in different patches, affect nutrient retention and output at a watershed level. My personal interests lay on riparian ecosystem, an area sits in between terrestrial upland and aquatics with dynamic biogeochemical processes, large seasonal variations, and unique species compositions.

Plant-Soil interactions and soil microbial ecology - My interests in microbial ecology are mainly due to its importance in explaining biogeochemical patterns. I am particularly interested in microbes responsible for mycorrhizal symbiosis, nitrification, methane production and consumption, and lignin decomposition.